Glass syringe having lettering embedded flush therein



April 1950 s. KOLODNY ETAL 2,505,411

cuss SYRINGE HAVING LETTERING EMBEDDED FLUSH THEREIN Filed May 11, 1949 INVENTORS SAMUE L KOLOD/VYK ATTORNEY Patented Apr. 25, 1950 GLASS SYRINGE HAVING LETTERING EMBEDDED FLUSH THEREIN Samuel Kolodny, Rutherford, and Nicholas Micci, Carlstadt, N. J., assiznors to East Rutherford Syringes, Inc., East Rutherford, N. .L, a corporation of New Jersey Application May 11, 1949, Serial No. 92,622

6 Claims. (Cl. 128-218) This invention relates to hypodermic syringes of the barrel and plunger type and, more particularly, to suchsyringes having volume or capacity indicia, and/ or other indicia, permanently integrated with the barrel and/r plunger.

These syringes are made of glass or other similar vitreous transparent material, and the barrel and plunger or piston are ground or otherwise finished to have a, precision fluid-tight fit with each other. This fit must be accurate, and great care must be exercised to insure a fluid-tight engagement of the parts, as such hypodermic syringes are precision instruments. To insure proper reassembly of the right plunger with the right barrel, after disassambly for sterilizing and the like, the two elements generally carry the same serial number or other identifying indicia.

To determine the amount of fluid drawn into the syringe, suitable volume indicating indicia are provided. These indicia generally comprise precision located graduations visible on the outer surface of the barrel, and registrable with the inner end of the plunger. The indicia comprise opaque pigmented material, and the inner end of the plunger may have the same material applied thereto for ready observation of its position relative to the graduations on the barrel. The latter may he graduated in cubic inches, cubic centimeters, or any other volume markings.

The markings of the opaque graduations on the barrel, and the application of identifying indicia to the barrel "and plunger, requires special techniques due to the nature of the syringe material and to the precision assembly of the syringe elements. In one known method of marking,the syringe element is coated with wax, the markings are engraved through the wax, and the engravings are etched with hydrofluoric acid or the like. The remaining wax is then removed, the etchings have ceramic paint applied therein, and the element is then baked to set the paint.

This is a complicated and expensive process,

I due to the number of operations involved, all of which must be performed with great care. Additionally, the paint may be scratched or chipped out of the etchings, making it difficult to read the markings.

In another process, a screen or stencil is applied to the surface of the element and ceramic paint is applied in the openings of the stencil or screen. The element is then baked to set the paint. This process provides markings which are raised above the surface of the element, and are very liable to removal-by scratching or chipping; Additionally,

, such markings cannot be applied to the surface markings.

of the plunger, for example, due to the close. flush surface fit between the plunger and the barrel.

Other processes of applying markings to vitreous articles are known, or have been suggested, but are inapplicable to precision instruments such as hypodermic syringes. For example, such other processes require heating of such a. character that the surface of the article is distorted. While this is not objectionable in such common articles as bottles, glasses, and the like, it is not permissible in hypodermic syringes. To maintain a pressure-tight seal between the barrel and plunger, there can be no distortion or either, and the inside diameter of the barrel and the outerside diameter of the plunger must be held to tolerances of less than 0.0001 in. Consequently, the aforementioned special techniques have been devised to obviate any distortion of the parts.

In the present invention, the defects of prior, marked hypodermic syringes are overcome and novel markings are provided which are integral Thus, opaque pigmented material is used for the markings and is flush with the surface of the syringe member while extending a substantial depth below such surface. The opaque material is integrated with the material of the member to an extent that the vitreous material must actually be ground away for a substantial depth to eliminate the This is effected by actually fusing ceramic pigment into the vitreous material for a substantial depth.

With the invention arrangement, the markings are flush with the surface of the syringe member, so that precision surface-to-surface engagement may be maintained. The markings cannot be scratched or chipped off, due to their flush relationship with the surface, and due to their integrated fusing or bonding with the surface. It is necessary to actually grind away the vitreous material or glass to remove the markings.

3 depth below the surface, and cannot be removed without removal of a substantial amount of the material forming the member.

These, and other objects, advantages and novel features of the invention will be apparent from 5 the following description andthe accompanying drawing. In the drawing:

Fig. 1 is a substantially enlarged elevation view of a hypodermic syringe embodying the invention.

Fig. 2 is a greatly enlarged longitudinal section of the barrel, taken on the line 2-2 of Fig. '1.

Referring to the drawing, the invention is illustrated as embodied in a hypodermic syringe l0 having a barrel or cylinder member 20 and a plunger or piston member 30. Members and are formed of a suitable transparent vitreous material, such as glass, and their interengaging surfaces are ground, or otherwise finished, so. that the members form a fluid-tight seal with 20 each other.

Barrel member 20 has an elongated cylindrical bore 2| open its full width at one end and communicated with a nozzle or the like 22 at the other end. The hypodermic needle is suitably secured to nozzle 22. At its rear end, member 20 may be formed with an enlargement or collar 23 which is useful as a grip in filling and discharging the syringe.

Plunger 30 has an axially elongated cylindri- 30 cal section 3| having a fluid-tight fit in bore 2|, and section 3| may be precision ground, as at 32, to assure such fit. Section 3| merges with a reduced neck 33 terminating in an enlarged knob 34 which may be gripped to operate the syringe. 35 The forward end 36 of section 3| is plane and perpendicular to the axis of the section.

As is usual in hypodermic syringes, barrel member 20 is provided with graduations 40 cooperable with the inner end 36 of plunger 30 to 40 indicate the amount of fluid within bore 2| between nozzle 22 and plunger face 36. Graduations 40 are volume indicia and, as shown, indicate cubic centimeters although other volume units may be used. The face 36 of plunger 30 may be suitably colored or otherwise processed to provide for easy comparison with the graduations 40. In addition to indicia 40, barrel member 20 may carry a serial number, or other identification 42 and the same identification 43 may be provided on plunger member 30. Thus association of the right plunger and barrel is assured.

Graduation indicia 40 and identification indicia 43, 42 constitute the novel feature of the present invention. These indicia are integrally bonded with the vitreous material of members 20 and 30 in such a manner that the indicia may be removed only by removing the surrounding vitreous material. Additionally, the outer surfaces of the indicia are flush with the surface of the member to which they are applied.

As illustrated more particularly in the enlarged section of Fig. 2, indicia 40, for example, are fused into barrel 20 for a substantial depth below the outer surface 26 of the barrel. Such depth may be of the order of 0.003 to 0.005 in., and the embedded indicia are permanently integrated with the material of barrel 20 so that it is necessary to grind surface 26 down from 0.003 to 0.005 in. to erase the indicia. 7

The latter have a life equal to that of the syringe. The outer surface 46 of each indicia 40 is flush with barrel surface 26, so that there is no projection of the indicia beyond surface 26. Hence, not only is accidental chipping or i in scratching of the indicia from the surface prevented, but also the resultant surface is flush so that the indicia may be applied to the surface of plunger 30 without interfering with its fluid-tight fit in bore 2|.

Indicia 40, 42 and .43 maybe applied in any desired manner capable of effecting a deep penetration of the indicia into the syringe member, an integral bonding thereof with the member, and a flush surface arrangement. For example, an opaque ceramic pigment, such as amber stain, may be mixed with a suitable liquid vehicle and the mixture applied to the surface of a syringe member through a special screen. After fusing, baking and annealing operations, the stain is fused into the glass to a substantial depth and is flush with the outer surface. The annealing corrects any possible distortion due to the fusing and baking steps.

As a result of thesesteps, permanent, visible, opaque markings or indicia are integrally fused into the surface of the syringe member to a substantial depth beneath said surface. These markings have outer surfaces flush with the external surface of the member, so that no disadvantageous efiect is produced on the precision fluid-tight fit of the members. The markings cannot be removed by scratching or chipping without destroying the syringe member.

The markings are applicable to any size hypodermic syringe, for example from 0.25 cc. to cc., and ranging from O. D. to 2.0" O. D. Their life is limited only by that of the syringe member to which they are applied, and they remain until the member is broken, or worn down or ground down a substantial depth. While one method of afiixing the indicia has been mentioned, other methods are feasible and the present invention is not limited to a particular operational sequence of method steps in applying the indicia.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles thereto, it

5 should be understood that the invention may be otherwise embodied without departing from such principles.

What is claimed is:

1. A hypodermic syringe comprising, in combination, a. barrel member; a plunger member slidably engaged in said barrel member; said members being formed of a transparent vitreous material and being finished to have a precision fluid-tight fit with each other; and opaque indicia along the outer surface of at least one 'of said members, said indicia comprising pigmented material bonded with such one member, and flush with and extending a substantial depth beneath such surface.

2. A hypodermic syringe comprising, in conibination, a barrel member; a plunger member slidably engaged in said barrel member; said members being formed of a transparent vitreous material and being finished to have a precision fluid-tight fit with each other; and opaque indicia along the outer surface of at least one of said members, said indicia comprising pigmented material fused with the material of such one member, and flush with and extending a substantial 0 depth beneath such surface.

3. A hypodermic syringe comprising, in combination, a barrel member; a plunger member slidably engaged in said barrel member; said members being formed of a transparent vitreous material and being finished to-have a precision fluid-tight fit with each other; volume indicia precisely positioned along the outer surface of said barrel member, said indicia comprising pigmented material fused with the material of such barrel member, and flush with and extending a substantial depth beneath such outer surface.

4. A hypodermic syringe comprising, in combination, a barrel member; a plunger member slidably engaged in said barrel member; said members being formed of a transparent vitreous material and being finished to have a precision fluid-tight fit with each other; and opaque indicia along the outer surface of at least one of said members, said indicia comprising pigmented material permanently integrated with the transparent vitreous material of such one member, and flush with and extending a substantial depth beneath such outer surface.

5. A hypodermic syringe comprising, in combination, a cylindrical glass barrel member; a cylindrical glass plunger member slidably engaged in said barrel member; said members being ground to have precision, fluid-tight engagement with each other; and opaque indicia along the outer surface of at least one of said members, said indicia comprising pigmented material permanently integrated with such one member, and

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 772,450 Wulfing-Luer Oct. 18, 1904 1,432,872 Kroehle Oct. 24, 1922 1,953,784 Strassner et a1 Apr. 3, 1936 

